Contributions to https://mwvsciencefair.wikispaces.com/ are licensed under a Creative Commons Attribution 3.0 License. 
Portions not contributed by visitors are Copyright 2018 Tangient LLC
TES: The largest network of teachers in the world
Portions not contributed by visitors are Copyright 2018 Tangient LLC
TES: The largest network of teachers in the world
Loading...
Table of Contents
Break it Down
Broad Question
Does a certain nutrient help vegetables decompose faster than another?Specific Question
Do cucumber skins decompose faster in phosphorus, magnesium, or potassium enriched sand?Hypothesis
It is hypothesized that the magnesium sulfate in the soil will cause the cucumber skins to decompose fastest.Graph of Hypothesis
Variables
Independent Variable:
The different nutrients: rock phosphate, potassium (Potash), and magnesium sulfate (Epsom Salts).Dependent Variable:
The dependent variable is the amount, in grams, that the cucumber skins have decomposed in each different sand.Variables That Need To Be Controlled:
Mass of all groups of cucumber skins.Mass of water put in each container.
Mass of each nutrient put in each container.
Mass of sand put in each container.
Water temperature should stay the same (22 degrees Celsius).
All containers must be placed in the same moist environment.
All cucumber skins cleaned in same way before massing.
All containers should be left for same period of time.
Same size and shape of containers.
All fresh European cucumber skins.
Vocabulary List That Needs Explanation
Potash: potassium or potassium compound often used in farming/crop productionRock Phosphate: a crystallized form of phosphorous, which is a nonmetallic element (is also often used in farming/crop production)
Magnesium Sulfate: a form of magnesium, (which is a white/silver metallic element), also used in farming/crop production
Epsom Salts: Bitter, white salt used as a laxative, but is also known as magnesium sulfate so it can be used in farming/crop production
Decomposition: to break down through chemical change
Reduction in mass: difference between initial mass and ending mass
General Plan
Potential Problems And Solutions
I need to get magnesium sulfate (Epsom Salts), potassium (Potash) and rock phosphate, which might be difficult and is something I need to research up on and order as soon as possible. The drying out of the cucumber skins will really affect their rate of decomposition so keeping them moist is crucial. I am going to seal them in an airtight plastic bag and fill it 2 inches high with water. It will be kept out of the sunlight too.Safety Or Environmental Concerns
Do not ingest potash or rock phosphate, but magnesium sulfate is okay to ingest, just not large amounts. It is recommended to wear safety goggles while using the nutrients to avoid getting dust in your eyes and wear rubber gloves. No health concerns with magnesium sulfate or potash but be cautious with rock phosphate.Experimental Design
The purpose of this experiment is to see which of three nutrients (rock phosphate, potassium, or magnesium sulfate) speed up decomposition of cucumber skins the most. The experiment will take place at JBES in the greenhouse, placed under the table to avoid sunlight. There are 3 groups of 5 containers, (a group for each nutrient), and each container has 200.0 ml of sand, 15.0 grams of cucumber skins, and 25.0 ml of its specific nutrient. After two weeks of being left the cucumber skins will be removed, massed with a gram scale, and then that mass will be subtracted by the starting mass,15.0 grams, to find the amount decomposed. The experiment will be controlled by using the same mass of sand, water and cucumber skins in each container, and water will be added when needed to prevent the skins from drying out. Images will be taken as the experiment progresses, for example of the setting up and of the ending results (before and after) and some in between.Resources and Budget Table
Detailed Procedure
1. Gather materials: 15 small plastic plant containers (252 centimeters cubed each), semi-coarse sand, European cucumber skins, and rock phosphate, potash, and magnesium sulfate.
2. Separate the 15 containers into three groups (5 in each). Tape paper towel onto the bottom of the containers so that the sand won’t sink through.
3. Add 200 milliliters of the semi-coarse sand to each container. When the containers are split into groups, take one of the groups of five containers and put 25 ml of the rock phosphate into each container. Take another group of five and put 25 ml of potash into each one. Then, take the last group of five and put 25 ml of magnesium sulfate into each container.
4. Stir the nutrient in each container so that the nutrient is mixed in well.
5. Pour 60 milliliters of water into each container evenly.
6. Take out the cucumber skins and make 15 groups of them that are all 15.0 grams. A scale will be needed; make sure the masses are exact.
7. Add 15.0 grams of cucumber skins to each container; bury them slightly in the soil.
8. Set the containers on a large tray and divide it into three sections and place 5 containers in each section; each divider should represent a nutrient. Then place a plastic bag over it all and fill the plastic bag with about four centimeters of water so it stays wet inside. Then, seal the bag so that it is airtight and the cucumber skins won’t dry out. Place it under the greenhouse table in the shade.
9. Leave the containers for two weeks.
10. Take out the containers and mass the cucumber skins, figuring out how much decomposed. The cucumber skins must be taken out gently (a metal ruler or some other thin sturdy device may be needed to scoop up the skins in case they are fragile) and most sand should be brushed off, and then they should be placed on a scale. Don’t mix the skins up.
11. Once data recording is finished, record final results in the data table and graph.
Photo List
1. Containers w/ paper towels2. Sand and sifter
3. Minerals (all)
4. Safety gear
5. Cucumber skins
6. Tray with containers and plastic bag
7. The whole plastic bag and tray under the table
8. A couple throughout-- not as important as before and after pics
9. Before and After pics of a nutrient container
10. Taking the containers out
11. Cucumber skins being massed
Data Table
Data Analysis
All Raw Data
Observations:Magnesium sulfate was the driest, was also the thinnest
Potash was the wettest, gooey
Rock phosphate was biggest, semi-dry
Sand on cucumber skins may have made a slight difference, but not a lot.
Graphs
Photos
Results
The average reduction of mass for the cucumber skins composted in rock phosphate was 11.7 (78%) grams. The average reduction for the cucumber skins in Potash was 11.2 (75%) grams. For the magnesium sulfate, the average reduction of mass for the cucumbers composted was 12.4 (83%) grams. The average reduction of mass for the cucumber skins composted in magnesium sulfate was largest, about 1.2 grams more than Potash which had the least decomposition.
Conclusion
The experiment was designed to test whether cucumber skins decompose fastest in one of three nutrient-enriched soils (rock phosphate, Potash, and magnesium sulfate). The results show that the nutrient with the least preserving qualities (magnesium sulfate) made the cucumbers decompose fastest, and the nutrient with the most preserving qualities (Potash) made the cucumber skins decompose slowest. The average reduction of mass for the cucumber skins composted in magnesium sulfate was 12.4 (83%) grams, 11.7 (78%) grams for the rock phosphate, and 11.2 (75%) grams for the Potash.
Discussion
The experiment was designed to test whether cucumber skins decompose faster in one of three nutrient-enriched soils: rock phosphate, Potash, or magnesium sulfate. It was hypothesized that the magnesium sulfate would allow the cucumber skins to decompose fastest, and the results supported that hypothesis. The average reduction of mass for the cucumber skins composted in rock phosphate was 11.7 grams (78%). The average reduction for the cucumber skins in Potash was 11.2 grams (75%). For the magnesium sulfate, the average reduction of mass for the cucumbers composted was 12.4 grams (83%). The average reduction of mass for the cucumber skins composted in magnesium sulfate was largest, about 1.2 grams more than Potash which had the least decomposition. Magnesium sulfate was the only nutrient found that didn’t appear to have any preservative qualities in it; it would follow that the bacteria could decompose the skins fastest in that environment. When researched, more forms of potassium were involved in preservation than magnesium sulfate, so the cucumber skins in Potash decomposed the least. Forms of rock phosphate were also involved in preservation, so it was the nutrient that decomposed the cucumber skins second fastest. The relationship between the three nutrients and decomposition of the cucumber skins was not strong because one nutrient did not decompose the skins at a much faster rate than another.
In the experiment it was realized that the drying out of the cucumber skins could drastically affect the results, so a plastic bag was sealed around the tray, which was then filled up to about four centimeters of water to create a consistent level of moisture and humidity. An early problem in the design was actually getting the nutrients, but a local farm supplies store had some left over from last year. Another problem was that when massing the skins, little grains of sand on them made a small difference in their final mass. After some research on the nutrients, it was realized that there were some health concerns, so goggles, face masks, and rubber gloves had to be found. At the end of the experiment, when the cucumber skins were to be taken out and massed, it was realized that the cucumber skins were fragile, so a metal ruler was used to pick up the cucumber skins. To improve the experiment there could have been bigger containers and a larger mass of cucumber skins in each one, making the difference of decomposition for each nutrient more significant. Also, it would have been helpful to take more pictures during the experiment to show the progress of decomposition. Technology-wise a camera was needed to take pictures of the food every time data was collected, and a scale that measured to a tenth of a gram. To carry out the experiment, information about composting in general, for instance where to put compost, how much water to add and what food can actually be composted should be known. Also it should be known what nutrients are related to plant growth, what they do for the plant, and where they can be bought.
The knowledge gained through this experiment could benefit people and this society because it helped show which of the three nutrients would help cucumber skins decompose fastest. This could help farmers who need to compost quickly, and for others starting a compost pile. Future questions and experiments could test if results are different with a different fruit or vegetable, or if the nutrients were put in a large compost with varied foods. This experiment could lead to further experiments of other ways to speed up decomposition and improve soil quality.
Background Research
NUTRIENTS AND WHERE TO BUY THEM:
$5.99 for a 4lb. bag of magnesium sulphate
$8.95 for a 2.2lb. (1KG) bag of potash powder
$15.11 for a 3lb. bag of rock phosphate
What does Magnesium do for plants?
Magnesium’s biggest role in plants is photosynthesis, because without it, chlorophyll cannot capture sun energy, and sun energy is required in the process of photosynthesis. Magnesium also helps with the stabilization of the plant.
What does Phosphorus do for plants?
Phosphorous is what makes flowers blossom and creates healthy leaves. It spreads and uses the light energy captured during photosynthesis.
What does Potassium do for plants?
Potassium helps plants become resistant to disease, fungi, and it also helps the plant to keep in water. Potassium aids phosphorus during photosynthesis and also helps make the stem of the plant sturdy.
According to last year’s science fair project, of grapefruit rinds, avocado peels, cucumber skins, and banana peels, cucumber skins decompose fastest. Here is the link to my data collecting and graph:
__https://docs.google.com/a/students.jbartlett.k12.nh.us/spreadsheet/ccc?key=0AmzmloHCKgObdDdaallNcjJxellManB5V1gwU3dENFE#gid=0__
Potassium also helps with preservation of foods:
"Common antimicrobial preservatives include sorbic acid and its salts, benzoic acid and its salts, calcium propionate, sodium nitrite (and sodium nitrate which converts to sodium nitrite "in situ"), sulfites (sulfur dioxide, sodium bisulfite, potassium hydrogen sulfite, etc.) and disodium EDTA.[1][2] Antioxidants include BHA, BHT, TBHQ and propyl gallate.[1] Other preservatives include ethanol and methylchloroisothiazolinone."
Phosphate also helps with preservation:
"Dicalcium phosphate, also known as calcium hydrogen orthophosphate, is used as an additive in foods. It is an artificially-made dietary supplement included by manufacturers to preserve organic products that might otherwise break down or lose integrity over long periods of time. The fellow additives monocalcium phosphate and tricalcium phosphate are closely related."
"Dicalcium phosphate falls within the class of molecules known as dibasic calcium phosphate. It contains two positively-charged calcium atoms and a phosphate molecule -- a normal phosphorus atom bonded to four oxygen atoms. These are very common organic elements. Phosphate, for example, links together parts of your DNA, and calcium, as the most common metal in your body, is used to perform muscle contractions and build bones."
WHEN RESEARCHED, MAGNESIUM SULFATE DID NOT APPEAR TO PLAY A PART IN PRESERVATION, AS THERE WAS NO RESEARCH REGARDING IT.
Sand has almost no nutrients because it is pretty much tiny rocks. Therefore it will be be perfect for my experiment's "soil" because it will not aid in the plants growth at all.
References
"Agronomic Library." Magnesium Basics. N.p., n.d. Web. 21 Mar. 2013.
Badger, Nina Isabel. "Science Fair Graph." Science Fair Graph. N.p., n.d. Web. 27 Mar. 2013.
"Definition of - Merriam-Webster's Student Dictionary." Definition of - Merriam-Webster's Student Dictionary. N.p., n.d. Web. 24 Mar. 2013.
"Definition of - Merriam-Webster's Student Dictionary." Definition of - Merriam-Webster's Student Dictionary. N.p., n.d. Web. 24 Mar. 2013.
"Definition of - Merriam-Webster's Student Dictionary." Definition of - Merriam-Webster's Student Dictionary. N.p., n.d. Web. 24 Mar. 2013.
"Dr. Earth 724 Soft Rock Phosphate 0-2-0 Boxed, 3-Pound." Amazon.com: : Patio, Lawn & Garden. N.p., n.d. Web. 27 Mar. 2013.
"Fixing Magnesium Deficiency in Plants: How Magnesium Affects Plant Growth."Gardening Know How. N.p., n.d. Web. 21 Mar. 2013.
"Plant Nutrients." Plant Nutrients. N.p., n.d. Web. 21 Mar. 2013.
"PotashAbout Our Definitions: All Forms of a Word (noun, Verb, Etc.) Are Now Displayed on One Page." Merriam-Webster. Merriam-Webster, n.d. Web. 24 Mar. 2013.
"Preservative." Wikipedia. Wikimedia Foundation, 21 Mar. 2013. Web. 21 Mar. 2013."
"Rite Green Magnesium Sulphate Soil Enhancer, 4-Lb." Rite Green Magnesium Sulphate Soil Enhancer, 4-Lb. N.p., n.d. Web. 27 Mar. 2013.
"Will the Nitrogen in My Miracle Gro Soil Affect Flowering." Growing. N.p., n.d. Web. 21 Mar. 2013.
__http://www.plants4perth.com.au/catalogue/garden-care/brunnings-potash-powder-2__ (could not parse)
Abstract
The purpose of this experiment was to see which of three nutrients (rock phosphate, potassium, or magnesium sulfate) sped up decomposition of cucumber skins the most. It was hypothesized that the magnesium sulfate would decompose the skins fastest. Three groups of five containers held sand, the specific nutrient, and cucumber skins. After two weeks, it was found that when massed, the fastest decomposer of the skins was magnesium sulfate (12.4 grams), then rock phosphate (11.7 grams), and 11.2 grams for Potash.